It is likely that your lens assembly was knocked out of alignment when you dropped the camera. When things do not line up inside the lens the whole unit cannot move in and out. This malfunction requires disassembly to fix, so you will have to get it to a professional for repair. There are providers online who can repair your camera, and also check with your manufacturer to see if they can service the camera at a reasonable rate. David Millier Advance Camera Repair
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